Mifenac Tablet

Mifenac is indicated for treatment of the signs and symptoms of osteoarthritis or rheumatoid arthritis in patients at high risk of developing NSAID-induced gastric and duodenal ulcers and their complications.

It is a combination product containing Diclofenac Sodium, a nonsteroidal anti-inflammatory drug (NSAID) with analgesic properties and Misoprostol, a gastrointestinal (GI) mucosal protective prostaglandin E 1 analog. The mechanism of action of Diclofenac Sodium, like other NSAIDs, is not completely understood but may be related to prostaglandin synthetase inhibition. NSAIDs inhibit prostaglandin synthesis. A deficiency of prostaglandins within the gastric and duodenal may lead to diminish bicarbonate and mucosal secretion and may contribute to mucosal damage caused by NSAIDs. Misoprostol can increase bicarbonate and mucous production & prevents gastric and duodenal ulcers.

Osteoarthritis: The recommended dosage for maximal GI mucosal protection is Diclofenac Sodium 50 mg & Misoprostol 200 µg tid. For patients who experience intolerance, Diclofenac Sodium 75 mg & Misoprostol 200 µg bid or Diclofenac Sodium 50 mg & Misoprostol 200 µg bid can be used.

Rheumatoid arthritis: The recommended dosage is Diclofenac Sodium 50 mg & Misoprostol 200 µg tid or qid. For patients who experience intolerance, Diclofenac Sodium 75 mg & Misoprostol 200 µg bid or Diclofenac Sodium 50 mg & Misoprostol 200 µg bid can be used.

Aspirin: Concomitant administration with aspirin is not recommended because Diclofenac Sodium is displaced from its binding sites by aspirin, resulting in lower plasma concentrations, peak plasma levels and AUC values.

Digoxin: Elevated digoxin levels have been reported in patients receiving digoxin and Diclofenac Sodium. Antihypertensives: NSAIDs can inhibit the activity of antihypertensives, including ACE inhibitors.

Warfarin: The effects of warfarin and NSAIDs on GI bleeding are synergistic, such that users of both drugs together have a risk of serious bleeding greater than users of either drug alone.

Oral hypoglycaemics: Diclofenac Sodium does not alter glucose metabolism in healthy people nor it alters the effects of oral hypoglycaemics. Diclofenac Sodium may alter diabetic patient’s response to insulin or oral hypoglycaemics.

Antacids: Antacids reduce the bioavailability of Misoprostol. Antacids may also delay absorption of Diclofenac Sodium.

Diuretics: The Diclofenac Sodium component like other NSAIDs, can inhibit the activity of diuretics. Concomitant therapy with potassium-sparing diuretics may be associated with increased serum potassium levels.

This is contraindicated in patients with hypersensitivity to Diclofenac, Misoprostol or to other prostaglandins. This should not be given to patients who have experienced asthma, urticaria or other allergic-type reactions after taking aspirin or other NSAIDs.

The most common reported side effects are abdominal pain, diarrhea and other GI symptoms. Diarrhea and abdominal pain developed early in the course of therapy and were usually self-limited (resolved after 2 to 7 days). Rare instances of profound diarrhea leading to  severe dehydration have been reported in patients receiving Misoprostol.

Because of the abortifacient property of the Misoprostol component, this is contraindicated in women who are pregnant. Diclofenac Sodium has been found in the milk of nursing mothers. Diclofenac Sodium plus Misoprostol is not recommended for use by nursing mothers.

Patients with an underlying condition such as inflammatory bowel disease or those in whom dehydration should be monitored carefully if Diclofenac Sodium plus Misoprostol is prescribed.

Paediatric use: Safety and effectiveness of Diclofenac Sodium and Misoprostol combination in paediatric patients have not been established.

Geriatric use: No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some elderly person cannot be ruled out. As with any NSAID, the elderly are likely to tolerate adverse events less well than younger patients.

Misoprostol: Convulsions, sedation, tremor, dyspnoea, diarrhoea, abdominal pain, fever, palpitations, hypotension, bradycardia. Management: Supportive treatment.

Diclofenac: Lethargy, drowsiness, nausea, vomiting, epigastric pain, GI bleeding. HTN, acute renal failure, resp depression, anaphylactoid reactions and coma may occur rarely

Drugs for Osteoarthritis, Drugs used for Rheumatoid Arthritis, Non-steroidal Anti-inflammatory Drugs (NSAIDs)

Store in a cool and dry place below 25º C. Protect from light.